This invention relates to inspection mirrors, and more particularly to handheld mirrors used to inspect inaccessible locations. Handheld inspection mirrors commonly utilize a flat glass mirror ( 1 to 2 inches in diameter) attached to a telescoping tube. This allows convenient storage in a shirt pocket, and permits access to remote places for observation after extension of the tube. These tools are used by many technicians, such as HVAC servicemen. However, prior art inspection mirrors produced an inverted image, which often results in misread model or serial numbers. Use of two mirrors at right angles has been proposed but this causes multiple images which are too confusing to be practical.
In geometrical optics terminology, a plane prior art mirror presents an inverted virtual image. The right angle prisms disclosed in this application are used as inspection mirrors for image correctness. The right angle prism employed as a porro prism in this invention presents an erect or non-inverted virtual image. The reflected image from two surfaces within the prism corrects the inverted image normally produced by a plane prior art mirror.